Casting machine for hemicylindrical printing plates



Oct. 31, 1933. H. FRITZ CASTING MACHINE FOR HEMICYLINDRICAL PRINTING PLATES Filed April 4. 1932 Fig 4.

5 Sheets-Sheet l Z-venl'or H. FRKTZ Oct. 31, 1933.

CASTING MACHINE FOR HEMICYLINDRICAL PRINTING PLATES Filed April 4, 1932 5 Sheets-Sheet 2 m 3 mm w 7;, van for yaw 4 Oct. 31, 1933. FRITZ 1,932,580

' CASTING MACHINE FOR HEMICYLINDRICAL PRINTING PLATES Filed April 4, 1932' 3 Sheets-Sheet 3 Fig.4.

which a roller 33 of the stop rests under spring pressure. The cog-wheel 31, is driven by a cogwheel 30 which is half the size of the cog-wheel and is mounted on the shaft 20; consequently, a rotation of the cam disc 31, 32 corresponds to one rotation of the gears 10 or 11, but two rotations of the shaft 20. As soon as the cam surface resting against the roller 33 is removed further from the centre of the cog-wheel 31, the stop 29 comes into engagement with the projection 27 or 28 of the locking member 26, namely in the casting position of the core, the projection 28 rests against the stop but in the withdrawn position of the core the projection 27 rests against the stop. Whereas the projection 28 is arrested by the stop exactly in the dead centre position of the disc cranks 10, 11, the arrest of the projection 2'7 by the stop causes the disengagement of the shaft 20 shortly after the other dead centre position of the disc cranks, i. c. after the removal members 69 have removed the plate 5 from the core and placed it on the table 12.

If, for instance, the stop 29 is withdrawn by hand and the projection 27, which has been arrested and until now as shown in Fig. 3, is re leased, the spring brings the tangential wedge into the operative position, that is to say couples the shaft 20 with the driving wheel 23. After a rotation of the wheel 23 through a little less than 360, the edge 28 comes into contact (as shown in Fig. 2) with the stop 29 which is actuated by the cam 32, and thereby uncouples the shaft 20 in the dead centre position of the gears 10, 11, until after the expiration of a certain time necessary for the casting and solidification of the plate by means of a device not shown, for instance a time gearing, the stop 29 is withdrawn consequently by the swinging of the locking member 26 due to spring tension the driving wheel is again coupled with the shaft 20. Together with the shaft 20, the cam surface 32 continues to turn and, after a rotation amounting to a little more than 180, before the edge 2'? passes by, springs forward against th stop thereof, whereby the shaft 20 is again uncoupled and the core is held in the position indicated in Fig. 3, i. e. after it has moved a short distance beyond the second dead centre position of gears 10 and 11.

The mode of operation of the plate casting machine according to the invention is as follows:

When the casting operation is finished, the core together with the plate is first of all withdrawn from the casting mould member 2 in a straight line, during which operation the matrix members 3 and 4 Withdraw the matrices from the plate in known manner, in order that they may be ready for the next casting. As soon as the plate 5 adhering to the core 1 comes out of the range of the matrix, the rollers 17 and 15 of the plate 14 come into engagement with the cam members 18 or 19. The plate 14 is thereby turned in clockwise direction and, together with the core, is swung through about 180. Shortly before the dead centre position of the gears 10 and 11 the rotary movement is ended, so that the core together With the plate 5 passes in a rectilinear movement by the four spring-controlled removal members 6, 7, 8, 9 which are sprung inwards and after passing the dead centre position of the gears, the core is returned to the casting mould member with the plate removed. In this operation the removal members hold the printing plate fast and after removal of the core hold it against the table 12 which is pressed flexibly against the core shortly before and after the dead centre positions of the gears 10, 11 and connected parts. After removal of the printing plate, the shaft 20 is uncoupled by the stop 29 and the projection 27, and the core 1 is held fast in the position indicated in Fig. 3 until a new matrix is inserted or until it is desired to proceed with the operation with the empty matrix. The plate 5 can safely be allowed to remain on the table 12 without the further operation being hindered. For the insertion of the core it is then sufficient to again withdraw the stop 29 by hand which releases the edge 27 and thereby couples the shaft 20 with the driving disc 23.

It is a Well known fact that in casting machines for round stereotype plate where the metal is delivered into the mould room through metal worms, the controlling of the worm is accomplished either so that an electromagnetic coupling, which is arranged between the motor and the worm, is put into operation at intervals, or else a valve which closes the metal elevating room is raised or lowered. In the one position the valve, by returning the transported metal renders the worm ineffective, in the other position it closes the worm so that the metal is brought forward into the casting form.

These two familiar controls by metal worm transporters are however, as practice has shown, subject to disturbances during operation. The electromagnetic coupling which is arranged between motor and worm is affected by the temperature of the hot melting furnace and plate casting which in some instances is put into operation also by an electric magnet is, like all valves in melting boilers, liable to get burned or encrusted by the metal. The invention in question removes the disadvantages of the two known devices. All apparatuses and mechanical parts employed are outside the steam protection cap of the melting furnace and can be placed anywhere one likes. This assures the working security so necessary for acasting machine and a perfect minding.

According to the invention the metal worm motor is rigidly connected with the worm elevator by a gearing. By this arrangement the motor does not run continually as with the before mentioned device, but is only switched on when metal should be transported into the casting room. Fig. 4 shows the switching diagram for the worm elevator motor. The motor is switched on by the mechanical operation of a push button so. In the latter part of its course into the casting position the casting core, by means of corresponding levers, switches on the push button switch 40. Thereby the time relay 41 and the remote switch 42 receives current, whereby the remote switch 42 jumps and closes the circuit to the motor. The time relay works on interruption i. e. after the elapse of an adjusted time the current for the remote switch is interrupted on contacts 43 and 4.4. As long as the core stands in casting position, button 40 remains pressed down. After the adjusted time the circuit of the remote switch is interrupted, it drops and interrupts the motor circuit. In consequence of the fact that the button 40 still remains pressed, the time relay is still under current, the circuit for the remote switch spool remains so long interrupted until the core by moving outward releases the button 40 and thereby interrupts the circuit for the time switch. The adjusted switching time correspond to the time for casting one plate. It is thereby possible to regulate the casting time by means of the time switch within desired limits. A new casting process only takes place'when the switch organs of the core again operate the switch 40. Switch 45) can be fitted on a part of the plate casting apparatus which is not exposed to the heat, while all other switching apparatuses are fitted on the switch board of the machine and are so no longer exposed to any damaging influences.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim. is: Y

1'. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for reciprocating the core in a straight line from operative relation with the mold to a delivery position and back again, and means for rotating the core about a vertical axis daring its travel from one of said positions to the 0 er.

2. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, a pin gear mounted coaxially with the core to rotate therewith, fixed cams cooperating with said pin gear to oscillate the core through an arc of 130 during each movement from one oi said positions to the other, said fixed cams including two rack-like members of different height facing each other and said pin gear having a long middle pin and two shorter lateral pins, the longer pin engaging both the rack-like cam members whereas the two shorter pins engage only the higher cam to move the middle pin out of dead center position.

3. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, said means including a driving shaft geared to the core, a driving disk on the shaft, a tangential wedge for clutching the disk to the shaft, resilient means holding the wedge in clutching position, means for rotating'the core about a vertical axis during its travel from one of said positions to the other, and means actuated by said driving shaft for unclutching the wedge when the core is in casting position and in delivery position respectively.

4. In a casting machine for hemicylindrical printing plates, .a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a deliveryposition and back again, said means including a driving shaft geared to the core, a driving disk on the shaft, a tangential wedge for clutching the disk to the shaft, resilient means holding the wedge in clutching position, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means actuated by said driving shaft for unclutching the wedge when the core is in casting position and in delivery position respectively, and means for engaging a printing plate on the core when the same is at the delivery position for removing the plate from the core.

5. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, said means including a driving shaft geared to the core, a driving disk on the shaft, a tangential wedge for clutching the disk to the shaft, resilient means holding the wedgein clutching position, means actuated by said driving shaft for unclutching the wedge when the core is in castingposition and in ole-'- livery position respectively, a pin gear coaxial with the core and traveling therewith, and fixed cams coacting with the pin gear to osciliate the core through an arc of 180 during its travel in either direction. I

6, In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a vdelivery position and-back again, said means including a driving shaft geared to the core, a driving disk on the a tangential wedge for clutching the disk to the shaft, resilient means holding the wedge in clutching position, means actuated by said driving shaft for unclutching the wedge when the core is in casting position and in delivery position respectively, a pin gear coaxial with the core and traveling therewith, fixed cams coacting with the pin gear to oscillate the core through an arc of 180'" during its travel in either irection, said cams comprising two rack-like members of different heightfacing each other and said pin gear having three pins of which the middle pin is longer than the other two, whereby the middle pin engages with both of the rack-like members while the two lateral shorter pins engage only the higher cam member to swing the middle pin out of dead center position. I

'7. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, said means including a driving shaft geared to the core, a driving disk on the shaft, a tangential wedge for clutching the disk to the shaft, resilient means holding the wedge in clutching position, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means actuated by said driving shaft for unclutching the wedge when the core is in casting position and in delivery position respectively, said unclutching means including radial projections fixed to the tangential Wedge, a cam disk, connections from said driving shaft for 'rotatingthe cam disk, and a stop moved by the cam disk in a direction radial to the driving shaft for engaging it with the respective projections to disengage the tangential wedge from the driving shaft at predetermined times.

8. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotatingthe core about a vertical axis during its travel from one of said positions to the other, and means for stopping the core shortly after the beginning of its return movement away from the delivery position.

9. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, and means for stopping the rotation of the core prior to the time of reversal of the movement of translation.

10. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, and means for stopping the rotary movement in each stroke before the movement of translation is completed.

11. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means for engaging a plate on the core when the same is at the delivery position for removing the plate from the core, and means for arresting the core shortly after said engaging devices have detached the plate from the core.

12. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means for engaging a plate on the core when the same is at the delivery position for removing the plate from the core, and means for stopping the rotation of the core prior to the time of reversal of the movement of translation.

13. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means for engaging a plate on the core when the same is at the delivery position for removing the plate from the core, and means for stopping the rotary movement of the core in each stroke before it reaches the point at which the motion of translation is reversed.

14. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, and means guiding the core for right-line movement during at least the beginning of its stroke in each direction.

15. In a casting machine for hemicylindrical printing plates, a stationary, vertical, mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means guiding the core for right-line movement during at least the beginning of its stroke in each direction, and means for stopping the rotary movement of the core before its movement of translation in either direction ceases.

16. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means guiding the core for right-line movement during at least the beginning of its stroke in each direction, and automatic means for seizing the plate uniformly at both sides when in delivery position and for stripping it off the core during such right-line movement of the core.

17. In a casting machine for hemicylindrical printing plates, a stationary vertical mold, a casting core, means for moving the core from operative relation with the mold to a delivery position and back again, means for rotating the core about a vertical axis during its travel from one of said positions to the other, means guiding the core for right-line movement during at least the beginning of its stroke in each direction, means for stopping the rotary movement of the core before its movement of translation in either direction ceases, and means for seizing the plate uniformly at both sides when in delivery position and for stripping it off the core during such right-line movement of the core.

18. In a casting machine for hemicylindrical 

